Means for controlling furnace combustion



Get. 29, 1935. E o C E 2,018,925

MEANS FOR CONTROLLING FURNACE COMBUSTION Filed July 10, 1934 2 Sheets-Sheet 1 I && N)

g N I a m Oct. 29, 1935. E. o. SCHEERER MEANS FOR CONTROLLING FURNACE COMBUSTION Filed July 10, 1934 2 Sheets-Sheet 2 MFZZMM,

Patented Oct. 29, 1935 UNITED STATES MEANS FOR CONTROLLING FURNACE COMBUSTION Ernest Otto Scheerer, Linden, N. J.

Application July 10, 1934, Serial No. 734,446

2 Claims. (01. 236-15) This invention relates to improvements in combustion controlling devices, and its leading object is to provide means for regulating the flow of air to the furnace, which will automatically operate to maintain a balanced mixture of air and fuel oil to the furnace.

Another object of the invention is to provide a governor for regulating the air flow to the furmace, and means for varying the regulating action of thegovernor, which is responsive to a fuel -oil flow actuated device.

Another object of the invention is to provide such a mechanism with means for varying the air regulating action of the governor, which is responsive to the variations of a carbon dioxide combustion indicator.

A further object of the invention is the provision of an air regulating governor, with a freely rotating disc adapted to turn independently of the governor, which is engaged by a shifting member, so that frictional resistance is not developed against the rotation of the governor, when the governor is subjected to a shifting action.

A still further object of the invention is the provision of a combined controlling device, which may be adapted to various types of oil burner furnaces, to control the combustion of fuel oil and air, without waste of fuel.

With the above and other objects in view the invention relates to certain new and useful constructions, combinations, and arrangements of parts, clearly described in the specification, and illustrated in the drawings, in which:

Fig. 1 is side elevation of the combined equipment.

Fig. 2 is a plan View thereof.

Fig. 3 is a vertical sectional view, taken on line 3-3 of Fig. 1, looking in the direction of the arrows. I

Fig. 4 is a similar view, taken on line 4-4 of Fig. 1, looking in the direction of the arrows.

Fig. 5 is a longitudinal sectional view, taken on line 5-5 of Fig. 2, looking in the direction of the arrows.

Fig. 6 is a detail sectional view through the blower, taken on line 66 of Fig. 4, looking in the direction of the arrows.

Fig. 7 is a similar view, taken on line I-I of Fig. 4, looking in the direction of the arrows.

Fig. 8 is a detail end view, showing the relay for operating the lever.

Fig. 9 is a transverse vertical sectional view, taken on line 9-9 of Fig. 5, looking in the direction of the arrows.

Fig. 10 is a detail vertical sectional view, taken on line I0-I0-of Fig. 5, looking in the direction of the arrows.

Fig. 11 is a detail vertical sectional view, taken on line I I-II of Fig. 5, looking in the direction of the arrows.

Referring to the drawings 5 designates an electric motor, the shaft 6 of which is extended or coupled to the shaft I of the air blower 8. The blower shaft is then extended horizontally and is supported in ball bearings 9, located distantly 5 of the blower, and carried by the bracket II].

On the blower shaft the air controlling shutter disc II is slidably mounted to move toward and away from the blower," and thus add increased and then reduced resistance to the flow 10 of air from the blower.

The air shutter disc II is mounted directly on the tube .I2, carried by the blower shaft and is connected to the four flexible governor springs I3, I4, I5 and I B. The opposite ends of the gov- 15 ernor springs are connected to the hub I1, which is connected to the end of the tube I8, also slidable on the blower shaft.

The adjacent ends of the shaft tubes I2 and it are spaced apart, and the end of the tube I2 is 20 equipped with a disc l9, formed with radial slots which receive the normally bowed springs of the governor, I3, I4, I5 and I6, to permit of unrestrained movement. The opposed end of the tube I8 is equipped with a similar disc 20, which is 25 formed with four similar radial slots, to receive the bowed governor springs. These opposed discs are prevented from relative rotative movement, by means of the key pins 2I, secured to the disc 20, and which slidably fit through openings in 30 the opposed disc I9, thus allowing for relative axial movement between the two discs, but effectively resisting relative rotative movement.

Each spring is equipped with a weight 22, located midway of its ends, for developing the required centrifugal pull during rotation. The hub I1 is equipped with a ball or roller bearing 23, on which floats the shifter disc 24. The position of this shifter disc on the blower shaft may be varied by means of the wheel nut 25, which is 4 threaded on the blower shaft.

The shifter-disc is operated by means of the shifter jaws 26 and 21, which are pivoted on the opposed arms 28 and 29, carried by the lever 30, which is fulcrumed at 3| to the base 32. This 5 lever includes the long arm 33, which is engaged by the small lever or cam 34, pivoted at 35 on an extension of the bearing bracket ID. The short lever or cam 34 is operated by means of the link 36 from the relay or intermediate motion 50 generating or transmitting device 31, which is connected by a controlling rod or tube 38 with the carbon dioxide indicator 39, which has suitable connections, as by the pipe 40, with the interior of the furnace, not shown, and which is re- 55 sponsive to changes in the oxygen conversion of the combustion taking place in the furnace.

The long arm of the lever is extended to receive the axial thrust rod 4|, of the pressure responsive device 42, which includes a conventional 30 I lever, with which the thrust rod 4| is in mechanical contact.

The short arm of the lever is pivotally connected to the link rod 45, which is pivoted to the auxiliary shutter lever 46. This lever 46 is connected by the link rod 41 with the lever 48,

which operates the auxiliaryshutter 49.. Another auxiliary shutter 50 is provided on the opposite side of the blower casing 5|, which has a lever 52, connected by the link rod 53 with the lever 48.

Should the oxygen consumption during the operation of the furnace drop below normal, the indicator 39 will operate to cause the relay 3'! to depress the long arm of the controlling lever, which will shift the shifter disc 24 away from the blower, thus causing the rotating governor weights and springs to produce a pulling effort on the circular shutter disc H, and thereby reducing the resistance to the discharge of the air from the blow, and of course increasing the output or discharge of the blower to the furnace.

Should there be an excess of air delivered tothe furnace the indicator 39 will register this, and will operate the relay 3'! andv thereby actuate the lever to cause a reverse movement of the shifter disc, so that the output of the blower to the fur.- nace is diminished. a

The discharge capacity of the blower is likewise balanced with the volume of fuel oil delivered to the furnace. If this volume increases, it will mean a greater discharge or flowing pressure, which will act upon the pressure responsive device to cause the rod H to operate the lever, to increase the discharge volume of air from the blower to the furnace.

The lever is engaged by'a coil spring 45, which serves to maintain the long arm of the operating lever elevated.

It is understood that any blower mechanism can be used, or any equivalent system for maintaining flowing air pressure to the furnace may be provided, instead.

The entire operation is automatic, and. functions without manual selective control, and serves to" maintain an efiicient mixture of the fuel oil sprayed or otherwise supplied to the furnace and the air supply, so that wastage of fuel is effectively prevented. If there is an excess of air therewill be a reduction in the temperature of the fuel oil as it enters the furnace, and an increase in the percentage of unconsumed fuel oil. If

there is insufiicient air the combustion of the fuel bined with all makes of oil furnaces and types of furnaces, and operates independently of the particular oil feed employed. 7

In addition to the operating means and'air controlling mechanism described, I may also provide an auxiliary or secondary air control, consisting of a damper or shutter 55, which is mounted adjacent to the furnace or properly associated with the air intake thereof, being suitably pivoted at 56 in place. This damper or shutter is opened and closed by means of the lever arm 51, which is engaged by the link rod 58, pivoted at one end to the lever and at the other .end to the long arm of" the main operating lever 30. The length of the 5 link rod 58 may be varied by means of the turnbuckle 59.

. When themain lever is rocked the secondary air control will also be operated, and the amount of air admitted with reference to the action of the 10 main lever 30, may be varied by means of the turnbuckle 59, the operation or turning of which will shorten or lengthen the link rod, so that any desired'relative action of the secondary or auxiliary air control may be obtained. g V 15 When the flow of oil is cut off the blower motor will also be cut ofi, so that the blast of air from the blower to the furnace will cease altogether, thus preventing the blower from continuing to discharge cool air into the furnace to cool the 20 same. The furnace heat will then be conserved for a longer period of time, so that when the operation of the furnace is again started the internal heat of the furnace, and the consequential rate of efficient combustion will be higher.

The governor regulated shutters control the flow of air through the intake openings of the blower, which discharges through the output tube Bla to the furnace. The length and arrangement of this discharge or output tube depends on the particular furnace installation.

When the shutters are in closed position, the air supply to the furnace is reduced, so that when the blower is not being driven, drafts through the furnace are diminished, and the internal heat 88 of the furnace walls will be conserved. As a result of this arrangement the furnace will retain its heat during an inactive period, as during night, and when again started the furnace will reach normal operating temperature in a shorter 40 period of time.

This conservation of the heat of the furnace, by the automatic prevention of free air flow through the furnace, when it is inactive, aifords opportunity to the owner or operator of the furnace to 45 maintain it in proper service, without waste of fuel. By conserving the internal heat of the furnace, which is stored up during its normal operation, less fuel is required to again start it with full service.

I claim as new:

1. The combination with a furnace blower, of a shutter for reducing the output of the blower, a governor mounted to rotate, with the rotor of the blower and connected to the shutter to operate the 5 same, a disc for operating the governor to cause it to vary its action on the shutter, a lever having means to engage the opposite sides of the disc, and means responsive to the presence of carbon dioxide gas for operating the lever.

2. The combination with a furnace blower having a shaft and a rotor thereon, of a governor adjustably connected at one end on the shaft and having a shiftable portion, a shutter connected r with the shiftable portion for varying the output 55 of the blower, a lever for varying the action of the governor relative to the shutter, a relay for operating the lever, a carbon dioxide detecter for operating the relay, and a device for operating the leverindependently of the relay which is re 70 sponsive to the pressure of fuel oil. 7

ERNEST OTTO SCHEERER. 

